The Pediatric Rheumatology Tissue Repository (PRTR) has been a funded component of a P30 Rheumatic Disease Core Center since 2001 and a major contributor to the past success of the P01 program. This core assists local and national investigators in specimen collection, processing, storage and distribution of biospecimens for rheumatic diseases-related studies. Because of the continued sample collection needs and special concerns in processing for the proposed P01 program, we are proposing to continue to fund a supplement to PRTR. The purpose of the supplement will be to expand the collection of patient and control samples to meet the needs of the 4 P01 projects. The scope of specimens needed for the P01 projects is extensive and can only be accomplished through collaborative efforts with additional clinical investigative sites (managed through the Admin Core). These new P01 collections will include blood (PAXgene tubes) DNA, serum, peripheral blood mononuclear cells, synovial fluid mononuclear cells and sorted cell subsets. RNA will be made from PAXgene samples, mononuclear cells and sorted cell populations. The tissue core will ensure uniform collection locally and nationally which is imperative due to the sensitivity of gene expression measurements. The tissue core will handle samples in a manner to protect patient confidentiality and to meet IRB requirements. Once collected, the tissue repository will be responsible for the distribution of samples to the individual projects or alternatively, the tissue repository will submit the samples directly to the Affymetrix core or the flow cytometry core for analysis. Established practices of the PRTR for sample collection, processing shipping and training of clinical site personnel ensure that the scope of specimens needed for the P01 research projects which are necessary to understand and define childhood rheumatic diseases are available.